drag method

void drag(
  1. double dx,
  2. double dy
)

Drags the map by dx, dy pixels.

Implementation

void drag(double dx, double dy) {
  var scale = pow(2.0, controller.zoom);
  final norm = controller.projection.toTileIndex(controller.center);

  final x = norm.x - (dx / tileSize) / scale;
  final y = norm.y - (dy / tileSize) / scale;

  final mon = TileIndex(x, y);

  controller.center = controller.projection.toLatLng(mon);
}